查询语句上的 Laravel 查询生成器错误

Question

我正在尝试从两个表中进行选择。从人员表需要名称和图像网址，从消息表需要用户发送/接收的最后一条消息。

在 people 中，人员 id 字段是唯一的，并且消息表具有人员 id。

我写了一个简单的查询来完成这个任务，但是当我在 laravel 中使用它时，它给了我一个错误，说“访问冲突”

这是我运行时有效的 sql 语句：

select people.id, people.first_name, people.last_name, people.img_url, user_messages.message, user_messages.created_at from people inner join user_messages on people.id = user_messages.people_id where people.user_id =1 group by people.id order by user_messages.created_at DESC

这是有错误的 Laravel 查询

$people = DB::table('people')->select('people.id','people.first_name','people.last_name','people.img_url' ,'user_messages.message','user_messages.created_at')
        ->join('user_messages','people.id','=','user_messages.people_id')
        ->where(['people.user_id' => $user_id])
        ->groupBy('people.id')
        ->orderBy('user_messages.created_at', 'desc')
        ->get();

如果我在 中包含所有字段，它不会向我显示错误消息，但随后选择了所有消息。

Answer 1

$people = DB::table('people')
    ->join('user_messages','people.id','=','user_messages.people_id')
    ->select('people.id','people.first_name','people.last_name','people.img_url' ,'user_messages.message','user_messages.created_at')
    ->where(['people.user_id' => $user_id])
    ->groupBy('people.id')
    ->orderBy('user_messages.created_at', 'desc')
    ->get();